The rapid expansion of information service and data processing industries has resulted in a need for computer systems to manage and store large amounts of data. As an example, financial service industry businesses such as banks, mutual fund companies or the like often operate large and complex data processing systems that require access to many hundreds of gigabytes or even terabytes of data. Data storage system developers have responded to these types of data storage requirements by integrating large capacity data storage systems, data communications devices and computer systems into networks called “storage networks” or “storage area networks” (SANs.) A storage area network is a collection of data storage systems that are networked with a number of host computer systems that operate as servers to access data stored in the data storage systems. Elements of a typical conventional storage area network implementation include one or more connectivity devices such as high speed data switches or routers that interconnect the various data storage systems to each other and to one or more host or server computer systems (servers) that require access to (e.g., read and/or write) the data in the data storage systems on behalf of client software applications and/or client computer systems.
Fully Automated Storage Tiering (FAST) is a storage system technology that automatically moves active data to high-performance storage tiers and inactive data to low-cost, high-capacity storage tiers. The result is higher performance, lower costs, and a denser footprint than conventional systems. FAST continuously monitors and identifies the activity level of data and automatically moves active data and inactive data to the most appropriate storage tier based on policy. Active data goes to the highest performance tier, and inactive data to the lowest-cost, highest-capacity tier. Policy settings enable administrators to control and manage automated activity.